Some people are spitting feathers over the prospect of chlorine-washed chicken being allowed to enter the UK for consumption under any post-Brexit trade deal with the US.

Across the pond, chicken carcasses are washed in chlorine to kill bacteria on the meat after slaughter and to reduce the risk of contamination from the bird’s digestive tract. However the practice is banned in the EU, although it states that it is safe to eat in moderation.

Environment secretary Michael Gove has said chlorine-washed chicken will not be allowed in the UK.

But there are some other US food standards that have not been addressed:

Higher levels of antibiotics in livestock

Livestock farmers in the US use higher levels of antibiotics – to promote growth or tackle disease – than their European counterparts. Therefore “their meat contains higher residues of those antibiotics,” says science policy professor Erik Millstone. There are fears that this could affect human resistance to the drug.

Beef cattle injected under the skin with growth hormones

US beef producers use implants of synthetic hormones under the skin of their beef cattle to promote growth. Essentially the animals need to eat less food and grow more quickly, making farming more competitive.

The EU does not think this is acceptably safe. According to briefing A food Brexit: time to get real, this is because the EU has wider considerations of safety, taking into account vulnerable groups such as pregnant women, young children and people with weak immune systems. On the other hand, the US only considers whether the hormone is safe for average healthy adults.

Spraying pig carcasses with lactic acid

This is done for the same reason that chickens are “washed” with chlorine. But while US abattoirs say it’s a beneficial way of cleaning carcasses, the EU thinks it can lead to poor hygiene standards.

Hormones that cause pain and suffering in dairy cows

US dairy farmers can inject their cows with the synthetic bovine growth hormone, called recombinant bovine somatotropin in the EU.

The ban in the EU – meaning that milk or dairy products from treated cows cannot legally be imported – is down to conclusions that the hormone affects the physical welfare of cows, and can cause them pain and suffering, the briefing reads.

‘Yoga mat’ chemical in flour

Azodicarbonamide is found in yoga mats and flour (Pixabay)

The US Food and Drug Administration (FDA) has approved the use of azodicarbonamide (ADA) in limited amounts for use as a whitening agent in cereal flour and as a dough conditioner in bread baking – it is also found in yoga mats and flip-flops.

The FDA acknowledges studies that show one of the breakdown products of ADA can be a carcinogen at high levels but says that “based on science, FDA is not recommending that consumers change their diets… [and] considers ADA a safe food additive when used for the purposes and at the levels specified in the FDA regulations”.

A number of fastfood chains in the US have phased out the use of ADA in their bread baking.

Arsenic in chickens

Arsenic is found naturally in the environment and it is also found in organic and inorganic forms, the latter of which is more harmful as a human carcinogen.

Organic arsenic is in the FDA approved animal drug known as Roxarsone, used for weight gain and improving pigmentation in chickens.

Following an FDA study that detected higher levels of inorganic arsenic in chickens treated with the drug compared to untreated birds, sales of Roxarsone have been suspended.

However the FDA says that because the levels were still very low, continuing to eating chicken does not cause a health risk.

Carcinogenic pesticides

We currently have EU-set “maximum residue levels” for pesticides in foods. These could be relaxed for any US-UK trade deal. Additionally, there are 82 pesticides on the EU banned list which are left off for the US. They include permethrin, which may be carcinogenic, and atrazine, a very commonly used insecticide, which has been linked with birth defects and the immune system, but for which research of its effect on humans has been inconclusive.

Food safety concerns

Food safety experts are concerned about the prospect of US food producers having unrestricted access to the UK market in any future trade deal.

“Not only would food safety standards deteriorate directly, but there would also be indirect adverse effects,” says Prof Millstone, one of the writers of the briefing. “This is because, in order to compete, UK producers would demand the right to use to same unsafe products and practices that are lawful in the USA.”

Unlabelled GM foods

He also raises the issue of different food labelling practices. Some hormones and ingredients are not declared on food labels in the US meaning that UK consumers will not necessarily know what they are eating.

“There are evident differences of view between UK cabinet ministers,” adds Prof Millstone. “Liam Fox would like to accept all US food products, while Michael Gove takes the opposite view. Theresa May has not yet taken sides in this dispute, but that is probably because she has not yet understood the complexities of the debate, let alone the urgency.”

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